Horizontal broaching machine



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Oct. 16, 1945. o. w. BNNAFE HORIZONTAL BROACI'ING MACHINE Filed Nov. 16, l942 oct. 16, 1945.

` o. w. BONNAFE HORIZONTAL BROACHING MACHINE Filed Nov. 16, 11942 3 Sheets-Sheet 2 O. W. BONNAFE HORIZONTAL BROACHING MACHINE oct. 16, 194s.

Filed Nov. 16,. 1942 s sheets-sheet 3 lll. T..

Patented Oct. 16, 1945 UNITED STATES PATENT-. oEFIcE 2,386,837T Y HORIZONTAL BRoAcmNG MACHINE Oliver W. Bonnafe, Hudson, Mass., assignor to The Lapointe Machine Tool Company, Hudson, Y Mass., a corporation of Maine Application November 16, 1942, Serial No. 465,779

11 Claims.

This invention relates to horizontal broaching machines in which a plurality of broaches yare drawn simultaneously Athrough a corresponding number of work pieces and in which the broaches are returned to initial position after the work pieces have been advanced out of broaching position. l Y

In the operation of such a broaching machine, the leading ends of the broaches are -rst inserted through the work rpieces and are locked to the main ram, which is thereafter actuated to pull the breaches through the work pieces for a breaching cut.

After' the broaches have entirely cleared the work pieces, the work holder is advanced one-half step to bring the work pieces out of alignment with the broaches and to bring the broaches into alignment with certain intermediate return tubes.

Themain ram is then reversed, pushing the broaches through the return tubes, whereupon the notched rear ends of the broaches are received and latched in a return puller slide. This slide is then withdrawn to complete the return movement of the breaches to a point where they entirely clear the work holder and the work pieces supported thereby.

The work holder is then advanced another half step to bring each work piece into alignment with the next broach inY the series, after which the puller slide is given a return movement to push the leading ends of all of the broaches through the work pieces to inserted positions in the main ram. The broaches are then locked in the ram and are drawn through the work pieces for a second breaching operation.

My present invention relates particularly to the construction and operation of thereturn; puller slide and of certain latching and locking devices associated therewith.

It is the general object of my invention to provide improved means for locking the broaches in the return puller slide prior to broach-return, and for unlocking the broaches. prior to a subsequent broaching operation..

To the attainment of this general object, I provide certain improved locking devices' which are simultaneously operative onA any number of' breaches within the capacity of the machine. I also provide improved operating mechanism for the locking devices, which mechanism is simple in construction and extremely reliable in operation and whichis definitely timed in relation to the movements of the return puller slide.

My. invention further relates to certain arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings-in, which Fig. 1 is a plan view, of a portion of 'a broaching machine embodying my invention;

Fig. 2 is a partial side elevation, looking in the direction of the arrow 2 in Fig. 1;

Fig. 3 is an end elevation, looking in the direction of the arrow 3 in Fig. 1; Y

Fig. 4vis an enlarged end elevation of'certain operating parts, looking in the directionv ofthe arrow 4 in Figs. 1 and 5;

Fig. 5is a sectional side elevation, taken along the line 5 5 in Figs. 1 and 4; v

Fig. 6 is a sectional side elevation, taken along the line 6 6 in Fig. 1; s l

Fig. `7 is an'enlarged sectional side elevation of the breach-holding Alatch and associated parts, taken along the line 'I-l in Fig. 1; and,` Vi

Fig. 8 is av view similar to Fig. 7 but showing the parts in unlocked position. f

That portion of the Vmachine which supports the work while the breachesl are pulled therethrough on a breaching cut is not shown in the drawings but is located at the right of the parts shown in Fig'. 1 and is disclosed in full detail in my prior application, Serial No. 410,461, filed September 1l, 1941.

For the purpose of this application;` it is sutucient to state that a plurality of work pieces are mounted in a rotatable work holder corresponding Vin number of workV stations to the number of puller heads in the broach-return mechanism shownA in the present application. The work. holderr further has broach-return tubes-between the work stations, andintermittently actuated feeding mechanism is provided by which the `work stations and return tubes are alternately aligned with the breaches. This work-holding and workfeeding apparatus forms no part of my present invention and isY thus' briefly described merely for lgeneral information as to the setting in which the lpresent invention operates.

'Referring to the drawings, I have shown portions ofthe iixed frame II) of a breaching machine having inwardly projecting guideways` II supported on th'e oppositeside walls thereof.v A return puller slide I4 is slidable in the guideways II and is actuated by a piston I5 (Fig.-2) movable in a xed hydraulic cylinder I6 and having a piston rod I'I. The rod Il is connected to the puller head slide by a bushing 20 (Fig. 5), slidable'ina bracket 2 I projecting downward from the slide I4.

The bushing is provided with a flange 22 at one end and is seated against a shoulder 23 on the piston rod I1 by a second bushing 25, pinned at 26 to the end of the piston rod and having an end flange 21. The flanges 22 and 21 are spaced to provide limited lost-motion for the bracket 2| between the flanges. On each reversal ofthe movement of the piston rod I1, this lost-motion must be taken up before the carriage I4 will be moved. It is this lost-motion which is utilized to operate the locking devices for the broaches in th'e return puller slide, as will be hereinafter described. v

As the broaches B (Figs. '7 and 8) are returned through the intermediate return tubes, the

notched rear end of each broach is received'in a return puller head 30, having a cylindrical opening 3l to receive a rotatably mounted broach support 32 in which' a latch 33 is pivoted. A spring 34 normally presses the latch against a stOp pin 36 in the support 32.

Each latch 33 has a depending lug 33 adapted to enter a notch 31 near the rear end of an associated broach B. The extreme rear end of the breach is preferably beveled, as indicated at 38 in Fig. 8, so that the broach may-be yieldingly inserted under the latch 33 by overcoming and compressing the spring 34.

. Each latch 33 hasfa conical recess 40 in its rear face to receive the adjacent conical end 4I of a locking` plunger 42, as shown in Fig. 7. When these plunsers 42. are in advanced or operative position, the latches ,33t-are looked so that the corresponding broaches cannot be yieldingly removed and so that, they may be drawn rearwerdbythe return puller slide.

Preservation of the exactn angular position of the broachesbeing important, the-latch holder 32 is provided with; a recess 44 (Fig. '1.) to receive the end o fa binding screw 4 5, and is also` provided with a milled or knurled flange 41. A suitable hand tool maylv be inserted through an opening. 48 t0 engage theflange 41 and move the support 32 angularly toa position in. which the lug 3S `of the latch 33 willbe accurately aligned with the? surface of the notch 31 in the associated breach A when the breach is in the desired angularv position. Th'eopening `48 may beplugged` or otherwise closed when not in use.Y The return pullerA heads 30 are mounted on tubular supports 50 (Fig. 1), the rear endsl of which supports are clamped in an4 annular member 5I which is mounted on a sleeve 52 (Fig. 5) whichis fixed in a bracketl 53 at the right-hand or forward end oi the slide I4, as sh'own in Figs. 1. land 2. A spacing disc 55 (Figs. 1 and 6) is provided to holdvthe puller heads 30 in equally spaced angular relation, but the heads 30 and associated parts are otherwise entirely supported by the bracket 53 on the slide I4.

. Attheir rear ends, the locking plungers42` extend through openings in a ring 60 (Fig. 5) mounted on a sleeve 6I slidable on a collar 62 secured to the rear orleft-hand end of th'e fixed sleeve 52 previously described. A spring 64,. is mountedV ony each plunger 42 between the ring 60 and a pair of adjustable lock nuts 65. Additional lockv nuts. 66 on the end of the plunger may be used. for accurately adjusting the plunger lengthwise.

TA lever 10, is pivoted oulav bearingy bracket 1I.I fixed to the slide I4 and has a pin-andslot connection vat its upper end to a cross. bar 14, which in turn 1s connected byV draw barsior bolts 15 tothe ring 60 previously described. At' its assess? lower end, the lever 10 has a pin-and-slot connection to the bushing 25 which is fixedly mounted on the rear end of the piston rod I1 Movement of the slide I4 to the left in Figs. 1 and 2 is limited by stop pins 11 yieldingly mounted in sockets in a frame member 18 secured to the end plate 19 of the frame I0 by a bolt 80. y

Having described the details of construction of my' improved return puller heads and associated parts, the operation thereof is as follows:

As the broaches B are moved rearward or to the left through their return tubes after a breaching stroke, the notched rear ends of the broaches enter the return puller heads 30 and yieldingly displace the latches 33 to reach the position shown in Fig. 8. Hydraulic pressure is then applied at the right-hand end of the cylinder I 6 to force the piston I5 and piston rod I1 to the left.

VThe first ell'ect of this piston rod actuation is to move the bushing 20 tothe left relative to the return. puller slide I4 and bracket 2| until the flange 22v positively engages the bracket 2I. Such. lost-motion movement of the piston rod I1 is effective through the lever 10 to simultaneously advance all of the locking plungers 42 from the position shown in Fig. 8 to the position shown in- Fig. '7, in which latter position all of the latches 33 are locked in holding position.

Continued actuation of the piston I5 and piston rod l1 then exerts direct pressure through the ilange 22 against the bracket 2l and slide I4, and the `slide I4 is moved to the left, thus drawing the broaches B to the left beyond the work pieces and out of the return tubes to extreme left-hand or withdrawn position.

After the work pieces have been advanced t0 their next broachng position, pressure is reversed in the cylinder I6, andthe piston I5 and, piston rod I1 are moved to the right in Fig. 1. The first effect of such movement is to draw the bushing 20 freely through the bracket 2I until the flange 21 engages the bracket. This relative movement or lost-motionA rocks the lever 10 to withdraw all of the plungers 42 from the locking position shown in Fig. '1 to the inoperative position shown in Fig. 8.

Continued movement of the piston I5 and pist0n rod l1 to the right then positively advances the bracket'll. and slide I4 and pushes the leading; ends of the broaches through the work pieces and into engagement with themain ram, to which they are then secured by additional locking devices', not shown.

During this advance movement of the broaches toward the main ram, the rear ends of the broaches are still engaged by the latches 33 but the latches are not locked, so that the broaches may be yieldingly pulled out'of the return puller heads as soon as the broaching operation is initiated by movement of the main ram.

The returnpuller heads and their associated parts then remain inthe described advanced position until the broaching operation is completed andl the work pieces are again moved out of broaching position. The broaches are then returned to the position shown in Fig. 8, after which the latches are again locked and the broachreturn cycle is repeated, all as previously described.

From the foregoing description it will be clear that the OperatioiflI 0f the locking plungers 42 is directly dependent on the lost-motion movement of the piston I1 relative to the bracket ZI. The latches 33 are thereby locked and unlocked in denite timed relation to the movements of the return puller slide. The latches are locked before the return movement of the slide and broaches and are unlocked just prior to the advance movement of the slide to return the breaches for connection to the main ram.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. In a broaching machine, a plurality of return puller heads, broach-engaging latches in said heads, locking devices for said latches, and means to actuate all of said devices to lock all of said latches before rearward movement of the puller heads begins and to unlock all of saidlatches before forward movement of the puller heads begms.

2. In a broaching machine, a return puller head, a broach-engaging latch in said head, a locking device for said latch, and means tc actuate said device to lock said latch before rearward movement of the puller head begins and to unlock said latch before forward movement of the puller head is completed.

3. In a broaching machine, a plurality of return puller heads, breach-engaging latches in said heads, locking devices for said latches, and means to actuate all of said devices to simultaneously lock all of said latches before rearward movement of the puller heads begins and to simultaneousll7 unlock all of said latches before forward movement of the puller heads is completed.

4. In a broaching machine, a return puller head, a broach-engaging latch in said head, a locking device for said latch, a slide on which said puller head is mounted, hydraulic actuating mechanism for said slide including a connecting rod having provision for a denite lost-motion between said rod and said slide, and means to alternately lock and unlock said latch, said latter means being operated by said connecting rod during lost-motion of said rod relative to said slide.

5. In a broaching machine, a plurality of return puller heads, broach-engaging latches in said heads, a slide on which said puller heads are mounted, hydraulic actuating mechanism for said slide including a connecting rod, a connecting device providing a denite lost-motion between said rod and said slide, and means to lock and unlock said latches, said latter means being operated by said connecting device during lost-motion of said rod and device relative to said slide.

6. In a broaching machine, a plurality of return puller heads, breach-engaging latches in said heads, a slide on which said puller heads are mounted, hydraulic actuating mechanism for said slide including a connecting rod having provision for a definite lost-motion between said rod and said slide, and means `to simultaneously lock and to simultaneously unlock all of said latches, said latter means being operated by said connecting rod during lost-motion of said rod relative to said slide and at each end of the path of travel of said slide.

'7. In a broaching machine, a plurality of return puller heads, broach-engaging latches in said heads, a slide on which said puller heads are mounted, hydraulic actuating mechanism for said slide including a connecting rod, provision for a denite lost-motion between said rod and said slide, and means to alternately lock and unlock all of said latches, said latter means being operated by said connecting rod during lost-motion of said rod relative to said slide and as said rod begins its travel in each direction.

8. In a broaching machine, a return puller head, a slide on which said head is mounted, a broach-engaging latch in said head, a locking plunger coacting with a recess in said latch to lock said latch, and means to advance said plunger to locking position as rearward travel of said slide is about to begin and to withdraw said plunger to unlocking position as forward travel of said slide is about to begin.

9. The combination in a broaching machine as set forth in claim 8, in which the locking plunger is actuated by a lever pivoted on the slide, and in which said lever is connected to an actuating rod which has a lost-motion connection to the slide.

10. In a broaching machine, a plurality of return puller heads, separate means to lock a broach in each head, a slide on which said puller heads are mounted, hydraulic actuating mechanism for said slide including a connecting rod having provision for a definite lost-motion between said rod and said slide, and actuating devices for said` locking means which are operated by said connecting rod during lost-motion of said rod relative to said slide and at each end of the path of travel of said slide.

11. In a broaching machine, a plurality of return puller heads, a slide, a support on said slide on which said heads are xed, a broachengaging latch in each head, a locking plunger for each latch, an annular member slidable on said support and to which each locking plunger is adjustably and yieldingly connected, means to move said slide alternately rearward and forward, and means to slide said annular member on said support forward before a rearward movement of said slide and rearward before a forward movement of said slide, whereby said breaches are alternately locked and unlocked in said heads.

OLIVER W. BONNAFE. 

